A description of the atom that is in accord with quantum mechanics is presented. This description explains the energy levels and line spectrum of the hydrogen atom and furnishes the basis of contemporary theory of chemical bonding. The electron position in the atom is considered in terms of probability, and the meaning of a 1s orbital is clarified with a digital computer plot, two analogies, and animation. The principal quantum number, n, is introduced together with its relation to energy levels, number of orbitals and the number of nodal surfaces.
Science Consultant: Prof. George C. Pimentel, University of California, Berkeley.